Superfund

Superfund is a term used for the monies available to the U.S.
Environmental Protection Agency (EPA) to clean up abandoned or inactive
hazardous waste sites. Such sites may involve soil and/or groundwater
contamination, and are often contaminated with
heavy metals,
such as arsenic, cadmium, chromium, lead, mercury, and zinc; pesticides,
including aldrin, dieldrin, chlordane, and
DDT
; and chlorinated solvents such as carbon tetrachloride, methylene
chloride, and tetra and trichloroethylene. Polychlorinated biphenyls (
PCBs
), cyanide, benzene, toluene, vinyl chloride, and radionuclides, including
strontium, plutonium, and uranium are also found at hazardous waste sites.
The $1.8 billion Superfund was established in 1980 by federal legislation
under the Comprehensive Environmental Response, Compensation, and
Liability Act (CERCLA). It was created with taxes imposed by the federal
government on major oil and chemical companies. At that time, common
belief was that sufficient funds and technology existed to clean up all
abandoned hazardous waste sites by 1985.

Historical Perspective

By 1985, although work had started at many sites, only approximately six
sites had been completely remediated, and it soon became clear that
revisions to legislation were needed to streamline cleanup efforts and
additional taxes for Superfund were required to provide funding. In 1986
Superfund was replenished under the Superfund Amendments and
Reauthorization Act (SARA). As a result of SARA, Superfund totaled $8.5
billion.

Under CERCLA and SARA, the EPA is given the authority and resources to
clean up hazardous waste sites. EPA's priority is to identify
responsible parties—those companies that have caused
contamination—and require them to clean up, at their own expense,
any corresponding hazardous waste sites. EPA thus reserves the use of
Superfund monies for sites in which responsible parties are not identified
or have claimed bankruptcy. As of 1999, responsible parties have
contributed over $16 billion toward the cleanup of hazardous waste sites.

The EPA follows a detailed procedure to evaluate hazardous waste sites and
ranks them according to the severity of risk to human health and the
environment. The national priorities list (NPL) includes those sites that
are deemed eligible for cleanup by Superfund. In 1987 it listed 1,187
sites and nearly 30,000 sites remained to be assessed. As of March 2002,
1,223 sites remained on the NPL and were eligible for cleanup under
Superfund. In addition, 810 sites had achieved "construction
completed" status which means that all the measures to clean up the
sites, as outlined in the EPA Record of Decisions, have been taken.

Site Cleanup Remedies

Technologies employed to clean up sites include procedures that have been
used for decades in treating water and air pollution; also, novel
techniques

Map illustrating Superfund sites in the United States, illustration.
(

Gale.

)

have been developed to clean up specific contaminants in groundwater and
soil. Environmental engineers, geologists, chemists, and biologists
consider alternatives to clean up sites depending on what medium is
contaminated (e.g., groundwater, surface or subsurface soil, surface
water, or air), and the nature of the contaminants. Community involvement
is also sought as part of the decision process.

Contaminants that are biodegradable may be completely converted to
environmentally acceptable products. An example of this would be using
microorganisms to biodegrade gasoline components in water or soil to
carbon dioxide and water. Alternatively, depending on cost and time
constraints, other technologies are employed that transfer the
contamination from one medium to another. Air stripping and soil vapor
extraction are examples of such technologies. Air stripping involves
spraying contaminated water into the top of a vertical tower while air is
pumped from the bottom to the top of the tower. Chemicals that are
volatile
will be transferred in the tower from the water to the air. In soil vapor
extraction, perforated pipes are drilled into contaminated subsurface soil
and a vacuum is applied to encourage volatile chemicals to transfer from
the soil to the air. Contaminants transferred to the air by these
processes, such as benzene, toluene, and trichloroethylene are sometimes
captured with activated carbon or destroyed by a combustion process, such
as incineration. Air stripping was employed to clean ground-water
contaminated with volatile organic chemicals, including trichloroethylene,
benzene, toluene, and xylenes, at the General Mills/Henkel Superfund site,
a former technical center and research laboratory in Minneapolis,
Minnesota. The contaminants in the ground water have stabilized since the
pump and treat system began in the early 1990s, with cleaned water being
discharged to the Minneapolis storm sewer system.

Since the inception of SARA, the EPA has expressed a preference for
cleanup remedies that destroy contamination rather than transfer it.
Contaminants may be destroyed by microorganisms that biodegrade chemicals
or by incineration processes that transform the chemical with extreme
heat. One billion pounds of contaminated soil were incinerated at the
Sikes Disposal Pits near Crosby, Texas, where hazardous waste from
petrochemical companies had been dumped in unlined pits during the 1960s.
The incineration was completed in 1994 and the site is now planted with
local grasses. The excavation of contaminated soil for hauling to a
landfill is an example of the removal and transfer of contamination to
another area. The concern with "removal technologies" is
that the contamination may create a future hazard to human health or the
environment. For this reason, the EPA has come to discourage the use of
removal technologies.

Pros, Cons, and Other Countries

Superfund's proponents argue that the EPA must have the authority
and resources to clean up hazardous waste sites. Otherwise, reluctant
responsible parties will have no incentive to bear the burden of cleanup.
In such cases, the protection of public health and remediation of damages
to the environment would be left for taxpayers to finance. Those against
Superfund reauthorization claim that many industries are responsibly
handling the matter of hazardous waste sites and have invested sizable
resources to clean up such locations. Furthermore, these industries have a
vested interest in achieving a cost-effective cleanup in a timely manner.

Many developed countries have implemented hazardous waste remediation
programs. Some countries pay for site cleanup from general government
revenues (taxes, etc.), whereas others rely on special taxes on industry
(similar to Superfund).

SUPERFUND SITE IN LIBBY, MONTANA

In Libby, Montana, the remediation of soil and groundwater contaminated
with pentachlorophenol (PCP) and polycyclic aromatic hydrocarbons (PAHs)
has been under way since 1985. PCP and PAHs are chemicals used to preserve
wood products such as telephone poles and railroad ties. The responsible
party, Champion International Corporation, caused soil and groundwater
contamination at its lumber and plywood mill in Libby. The EPA determined
that wastewater and sludge from the wood-treating process were the sources
of contamination. To address the issue of contamination, drinking water
from a public water supply was provided to residents of the Libby area,
and the use of private wells prohibited. Contaminated soil and groundwater
are undergoing cleanup using bioremediation, a technology that employs
microorganisms to transform hazardous chemicals into environmentally
acceptable products.

User Contributions:

Comment about this article, ask questions, or add new information about this topic: